This application provides methods, compositions for identifying and using maintenance genes. The methods and compositions have extensive practical applications in areas such as drug discovery and diagnostics.
Housekeeping genes, or maintenance genes, are those genes constitutively expressed to maintain cellular function (See, Watson, J. D., N. H. Hopkins, J. W. Roberts, J. A. Steitz, A. M. Weiner, A. M. Molecular Biology of the Gene, Vol. 1, 1965).
Previously tons of genes have been reported as putative housekeeping genes. The genes previously reported were identified by conventional methods and the putative housekeeping role of the gene product is an incidental observation (Duhig, T., C.
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Cloning of a Housekeeping-Type Gene (MER5) Preferentially Expressed in Murine Erythroleukemia Cells.Gene 80 2:337-343, 1989).
Recently, massive parallel gene expression monitoring methods have been developed to monitor the expression of a large number of genes using nucleic acid array technology which was described in detail in, for example, U.S. Pat. Nos. 5,871,928, 5,800,992 and 6,040,138; de Saizieu, et al., 1998, Bacteria Transcript Imaging by Hybridization of total RNA to Oligonucleotide Arrays, NATURE BIOTECHNOLOGY, 16:45-48; Wodicka et al., 1997, Genome-wide Expression Monitoring in Saccharomyces cerevisiae, NATURE BIOTECHNOLOGY 15:1359-1367; Lockhart et al., 1996, Expression Monitoring by Hybridization to High Density Oligonucleotide Arrays. NATURE BIOTECHNOLOGY 14:1675-1680; Lander, 1999, Array of Hope, NATURE-GENETICS, 21(suppl.), at 3.